Causes of Sciatica

Herniated Disc (90% of cases)

The main cause of sciatica. L4-L5 herniation compresses the L5 root: pain along the lateral thigh, calf, dorsum of the foot, numbness of the big toe. L5-S1 herniation compresses the S1 root: pain along the posterior thigh, calf, lateral foot margin, weakness of plantar flexion. Central herniation may compress both roots.

→ Disc Herniation Regenerative treatment

Spinal Stenosis

Narrowing of the spinal canal or foraminal openings. Characteristic: pain and numbness in both legs when walking, relief with forward flexion and sitting (neurogenic claudication). Unlike herniation — bilateral involvement and association with walking distance.

→ Stenosis Treatment

Spondylolisthesis

Forward slippage of a vertebra. Degenerative (L4-L5 in the elderly) or isthmic (L5-S1 in young athletes). Compression of neural structures at the site of slippage. Pain worsens with extension and prolonged standing.

→ Spondylolisthesis Treatment

Piriformis Syndrome

Spasm of the piriformis muscle compresses the sciatic nerve in the infrapiriform space. Pain in the buttock with radiation along the posterior thigh. Worsens with prolonged sitting. Spinal MRI shows no pathology — this is "pseudo-sciatica." Diagnosis: tenderness on palpation of the piriformis muscle, Freiberg test, FAIR test.

Facet Joint Syndrome with Root Compression

Hypertrophied facet joints and osteophytes narrow the foraminal opening. Pain on lumbar extension, radiation to the leg. Distinction from discogenic sciatica: pain worsens with extension (not flexion).

→ Facet Joint Syndrome Treatment

Pain Characteristics by Level of Involvement

L4 Root (L3-L4 Herniation)

Pain: anterior thigh, medial calf. Numbness: anteromedial calf. Weakness: knee extension (quadriceps). Reflex: reduced knee reflex. Frequency: 5% of sciaticas.

L5 Root (L4-L5 Herniation)

Pain: buttock, lateral thigh and calf, dorsum of foot. Numbness: lateral calf, first-second interspace. Weakness: big toe extension, foot dorsiflexion. Reflex: unchanged. Frequency: 45%.

S1 Root (L5-S1 Herniation)

Pain: buttock, posterior thigh, calf, lateral foot margin. Numbness: heel, lateral foot, little toe. Weakness: plantar flexion (inability to rise on toes). Reflex: reduced Achilles reflex. Frequency: 50%.

Red Flags

Cauda Equina Syndrome

Bilateral sciatica + perineal numbness + urinary/defecatory dysfunction. Emergency decompression within 24-48 hours. Delay leads to irreversible damage.

Progressive Foot Drop

Worsening "foot drop" — inability to lift the foot and toes. Sign of progressive L5 root compression.

Sciatica + Fever

Back pain with radiation + fever — epidural abscess or spondylodiscitis possible. Emergency MRI with contrast.

How it is treated: the cause comes first

Treatment depends on the cause of the pain, so it starts with an examination and, if needed, imaging — X-ray, ultrasound or MRI. The same pain can be caused by osteoarthritis or by a tendon, nerve or disc problem.

Most patients are helped by conservative treatment: exercise therapy, load management, short courses of painkillers and sometimes injections. Regenerative methods (PRP, cell preparations) are discussed once the diagnosis is known and there is at least limited evidence for it; no method guarantees a result.

We send a description of your case and your images to several partner clinics. The clinic doctors give a preliminary opinion, suggest a plan and quote a price, and we help you compare the options.

Who it is not suitable for and possible risks

Contraindications

  • Active infection — at the injection site or systemic, with fever.
  • Active cancer or ongoing chemotherapy.
  • Blood clotting disorders or a low platelet count. Anticoagulants are discussed with the physician.
  • Pregnancy and breastfeeding — the procedure is usually postponed.
  • A corticosteroid injection into the same area in recent weeks.
  • Urgent surgery, not injections, is needed if there is progressive leg weakness, numbness in the groin area or bladder dysfunction.

Possible risks

  • Pain and swelling at the injection site for 1–3 days.
  • Bruising where blood or fat tissue is taken.
  • Rarely, infection. The procedure is therefore performed under sterile conditions with ultrasound or X-ray guidance.
  • The effect may be absent or smaller than expected.
  • Injections into the intervertebral disc carry a rare risk of disc inflammation (discitis).

If any of these apply to you, mention it in your request. The coordinator will check with the clinic physician whether treatment is possible. Contact a coordinator.

Scientific evidence

Studies of regenerative methods show mixed results. Clinic physicians rely on research including the following:

  1. Lurie JD et al. Surgical versus nonoperative treatment for lumbar disc herniation: eight-year results for the spine patient outcomes research trial. Spine (Phila Pa 1976), 2014.
  2. Bailey CS et al. Surgery versus Conservative Care for Persistent Sciatica Lasting 4 to 12 Months. N Engl J Med, 2020.

Next steps: Treatment methods · Treatment cost · How treatment in Germany is organised · Contact a coordinator

Questions about Sciatica

How to distinguish sciatica from regular leg pain?

Sciatica is shooting, burning pain from the lower back along the posterior thigh to the foot. Worsens with coughing, sneezing, bending. Regular muscle pain is dull, local, without radiation below the knee.

Can sciatica be cured without surgery?

Yes, in most patients: radicular pain usually eases noticeably within 6–12 weeks, and the herniation itself often shrinks over time. Activity, exercise therapy, painkillers and, for severe pain, a periradicular or epidural injection help. Surgery is discussed for increasing leg weakness, bladder or bowel problems or severe pain that persists despite treatment.

How long does sciatica last?

An acute episode usually lasts from a few weeks to 2–3 months, and in most people pain eases noticeably within 6–12 weeks. In some patients the pain becomes chronic or recurs. If there is no improvement after 6 weeks, or weakness and sensory changes appear, an MRI and medical examination are needed.

Can you exercise with sciatica?

In the acute phase take it easy but avoid bed rest: walk as comfort allows. Then gradually add exercise that does not worsen the leg pain — walking, swimming, core exercises. Running, jumping, heavy lifting and deep bending are postponed until the radicular pain settles; after an injection the physician usually recommends 1–2 days of rest.

What tests are needed?

Lumbar MRI — mandatory. EMG — for numbness and weakness in the leg (determines level and degree of damage). X-ray — if spondylolisthesis suspected.